Science Matters: Glimmers Of Hope For Treating ALS

Much of the buzz at the annual meeting of the American Academy of Neurology (AAN) in early May was around competitive drugs for treating spinal muscular atrophy (SMA), including Biogen Inc.’s Spinraza (nusinersen). Biogen also presented late-breaking interim data from a Phase I/II clinical trial of its antisense amyotrophic lateral sclerosis (ALS) drug candidate tofersen (BIIB067). Only 2% or so of the ALS patient population has a mutation in the superoxide dismutase 1 (SOD1) gene, the target of tofersen. But the tofersen data, coupled with the success of Spinraza, which is also an antisense oligonucleotide (ASO) aimed at a gene mutation affecting neurons, are encouraging signs that targeting genetic drivers of ALS with ASOs or other gene-altering drugs could halt progression of several forms of the disease.

The tofersen data, while preliminary, provided assurance that the drug hits its target and is consistent with the belief that it may slow disease progression. Ten people who were given...